OF COPPER. 389 



11. Formate of copper. This salt has a Formate, 

 greenish blue colour, and forms flat six-sided 

 prisms terminated by four-sided pyramids. Its 

 constituents, from Berzelius' analysis, appear to 

 be 



1 atom formic acid . 4'625 



1 atom oxide of copper 5 



4 atoms water . . 4'5 



14-125 



From the preceding list, which includes a con- 

 siderable number of native cupreous salts, it ap- 

 pears that most of the salts of this genus contain 

 water of crystallization. In general the quanti- 

 ty of water is small, for more than half the salts 

 in the list contain only 1, 2, or 3 atoms. One 

 of the carbonates and one of the phosphates are 

 anhydrous green dicarbonate, a phosphate, ace- 

 tate, and oxalate, contain 1 atom chromate and 

 trisacetate contain 2 atoms two arseniates, sub- 

 sesquacetate and tartrate, 3 an arseniate and 

 formate 4 sulphate 5 nn arseniate and verdi- 

 gris 6 nitrate 7 an arseniate 18. With the 

 exception of this last arseniate, 7 is the greatest 

 number of atoms of water in any cupreous salt 

 hitherto analyzed. 



18. SALTS OF BISMUTH. 



1 . Sulphate of bismuth. This salt is usually Sulphate, 

 in the state of a white powder, though it may be 



Bb3 



